The Conquest — Jude Deveraux

Lovely 17-year-old Zared Peregrine is the pride of her family, a treasure her rough-hewn brothers, Rogan and Severn, will strive at any cost to protect from their ancient enemies, the Howards. The Peregrines have suffered loss enough in this blood feud --- their mother, father, four other brothers, and very nearly Liana, Rogan's wife. Fearing they may lose their beloved little sister as well, Rogan and Severn train Zared in the arts of war and dress her in boys' clothing --- but refuse to allow her to venture outside their fortress alone. So no one knows that they youngest Peregrine is a girl.

Yet when the magnificent knight Tearle Howard returns from a lengthy sojourn in France, it takes him but a glance to realize that Zared is most definitely female --- and beautiful. Handsome, dark-eyed Tearle knows he wants Zared from the moment he sees her. And Zared, foolishly, makes his conquest simple: a girl raised with a sword in her hand is not easily sequestered behind castle walls. So as the enmity between their families rages on, Tearle mounts a bold campaign to win the ravishing spitfire's heart --- and save her from the dark feud that threatens Zared's life.